This invention relates in general to adjustable seats and in particular to vehicle seats whose position may be adjusted fore and aft.
Vehicles, such as passenger cars, typically include seats for the use of a driver and other occupants. In many vehicles, the position of the seats may be adjusted for the comfort of the driver or the occupant. The options to adjust the position of a seat typically include the ability to move the seat fore and aft. To accomplish this movement, the seat commonly includes a seat adjuster assembly having a pair of track assemblies mounted under a seat bottom of the seat. One track assembly is mounted on the inboard side of the seat and the other track assembly is mounted on the outboard side of the seat. Each of the track assemblies includes an upper track which slides relative to a lower track. The upper tracks are attached to the seat bottom. The lower tracks are attached to the floor of the vehicle. A latching or locking mechanism is typically provided in or on each of the track assemblies which includes locking members which selectively lock the upper track relative to the respective lower track. To adjust the fore and aft position of the seat, the locking mechanisms are actuated to unlock the track assemblies. The seat is then moved to a desired position. The locking mechanisms are then actuated to their locked position. The locking mechanisms often include triggers pivotally mounted on one of the upper and lower tracks. The triggers have a plurality of teeth which are selectively disposed in slots formed in the other of the respective upper and lower track to lock the locking mechanism. The triggers are connected to a handle or towel bar which is pulled by the occupant or other user of the seat to lock and unlock the teeth of the triggers within the corresponding slots.
There is illustrated in FIGS. 13 through 15 a prior art outboard upper track assembly, indicated generally at 500. The upper track assembly includes a first track member 502 and a second track member 504. The members 502 and 504 are formed from stamped plates and are attached together. Sandwiched between the members 502 and 504 is a generally flat outboard trigger 510 having a plurality of teeth 512 that selective engage with a plurality of apertures (not shown) in a lower track assembly (not shown). The outboard trigger 510 is pivotally attached to the first and second track members 502 and 504 when assembled and pivots about a pivot 514. A lever 520 is pivotally attached to the members 502 and 504 when assembled and pivots about a pivot 522. The lever 520 has a lateral extension 522′ which is connected with a pull handle or towel bar (not shown) which is rotated by the occupant or user of the seat to lock and unlock the outboard upper track assembly. The lever 520 includes a slot 524 that receives a rounded end 526 of the trigger 510 such that pivoting of the lever 520 in a first rotational direction will cause pivoting of the trigger 510 in a second rotational direction opposite the first rotational direction. Rotation of the trigger 510 either lifts or seats the teeth 512 with the corresponding apertures of the lower track member (not shown). There is illustrated in FIG. 16 a prior art inboard upper track assembly, indicated generally at 540. The inboard upper track assembly 540 is similar to the outboard upper track assembly 500 and includes a first track member 542, a second track member 544, a trigger 546, and a lever 548. The trigger 546 is pivotally attached to the members 542 and 544 at a pivot 550. The trigger 546 includes a rounded end 552 which is received in a slot 554 of the lever 548. The lever 548 is pivotally attached to the members 542 and 544 at a pivot 558. The lever 548 has a lateral extension 549 which is connected with the towel bar (not shown) connected to the lateral extension 523 such that the lateral extensions 523 and 549 are connected together.
A distance A between the pivot 522 and the slot 524 of the outboard lever 520 is greater than a distance C between the pivot 558 and the slot 554 of the inboard lever 548. A distance B between the rounded end 526 and the pivot 514 of the outboard trigger 510 is less than a distance D between the rounded end 552 and the pivot 550 of the inboard trigger 546. These different dimensions, A, B, C, and D enable the inboard trigger 546 to pivot at a faster rate than the outboard trigger 510 when rotated by their cooperating levers 548 and 520, respectively. This arrangement is desirable when a seat belt load attachment point acts on the inboard track assembly 540 but not the outboard track assembly 500.